Friday, December 16, 2016

 Nuclear is Not the Answer

George M. Woodwell

December 2016

            The remains of the Chernobyl reactor in the Ukraine have been sealed  recently with a giant steel cap constructed at a distance and moved into position over the still highly radioactive reactor core. The reactor exploded on April 26, 1986, more than 30 years ago.  The site and its environs, many square miles, were heavily contaminated at the time. The remains of the reactor are still a festering hazard and will be dangerous substantially forever. The site, now expensively covered to contain the radioactive debris, constitutes yet another segment of a finite and already densely occupied Earth, sacrificed to a failed industrial venture.   

            Ionizing radiation is a biological hazard because it breaks up molecules and makes them chemically active. Chromosomes are large and especially vulnerable. Human exposures of any intensity at all puts the integrity of the genetic structure at hazard. It increases the frequency of mutations, not an attractive or even acceptable circumstance. Exposures can be external as from an xray machine or from a segment of a reactor core after an accident, or from radioactive particles incorporated into tissues. Both routes are of continuing concern at Chernobyl and the giant cover is designed to contain all the hazards of the reactor site.  It does nothing of course to restore the vast areas contaminated with radioactive debris at the time of the explosion.

            Meanwhile, global industries struggle with the necessity for replacing fossil fuels as the principal source of energy driving an energy –dependent industrial world.  Nuclear power is attractive to some because it appears to offer large sources of electrical energy without releasing carbon dioxide or methane, both heat trapping gases and the cause of the climatic disruption. The industry also appears to be a mature in that there are now about 400 reactors operating in the world, presumably safely, despite the inherent dangers of radioactivity.  Those dangers, especially the hazards to the human genome, make the fuel cycle and operation of the reactors necessarily “closed” systems that, at least nominally, contain all wastes and other radiation hazards.

 “Closing” the system, while necessary, is difficult to the point of impossibility. There is leakage and a series of  hazards at virtually every stage starting with the open-air mining of the uranium ore, its transportation, refinement, and  continuing through to the disposal and storage of used reactor  fuel rods and associated equipment. Accidents are inevitable at every stage and the wastes accumulate and must be accommodated. The system, carefully monitored as it is, cannot be perfect.  Although it is the model of a closed industrial system, it is not closed and cannot be made so.

 Despite major efforts, the United States has not been able to establish a long-term burial site or other safe disposal for radioactive wastes.   Used fuel rods, highly radioactive, are now cooled continuously in special water-cooled tanks at each reactor, a “temporary” solution used for decades.  The long-term burial site at Yucca Mountain in Nevada has proven unsatisfactory because of potential leaks and political objections.

While we do make compromises as a matter of necessity, we assume correctly that low exposures are safer than high exposures and carefully limit all exposures.  And we aspire to keeping the industry as a closed system, in fact the model of a closed system, thereby protecting the integrity of the human genetic system.

Closure must be perfect, but it cannot be so. Even containment is difficult. Worse, there is no way to avoid the possibility of using the enriched uranium designed for reactor use as the basis for developing bombs of various types ranging from a simple rain of radioactive debris in a ‘dirty’ bomb to a nuclear weapon.  There is no way of policing an increasingly crowded world of 7-10 billion people to keep the highly toxic wastes of a proliferating nuclear power industry safely contained.

            The attractiveness of large reactors is understandable, especially if one takes the perspective of an industry that generates and sells electricity.  A large central source of electricity distributed over extensive power lines to thousands of users is an attractive investment.  If fossil fueled plants are to be avoided, as is now clearly necessary, a nuclear-powered plant might confer some of the same advantages and feed the same delivery system.  So the arguments in favor of nuclear power emerge repeatedly despite the complexities of the industry. 

            One of the possibilities often advanced is the development of small “fail-safe” reactors that can be scattered over the landscape close to points of major demand. These reactors present the same set of issue, if smaller scale than large reactors.  Both, when operated, mark a spot on the earth that is from that moment on irrevocably committed to continuous care in protecting the public from radioactive debris, a very expensive “sacrifice zone” not available for any other use.

            Economic gradients favor common sense in this instance. Nuclear power plants are  expensive to build and require years for construction as well as extraordinary efforts in assuring safety. The energy involved in the mining, transport and refining of fuels, and  in virtually all other aspects of construction and maintenance, is fossil fuels, not a trifling matter   By comparison with rapidly emerging renewable energy sources that can be widely dispersed and require little maintenance, nuclear fails again.   As techniques for storage of electricity improve and the efficiency and variety of renewable sources of energy increase, the interest in and viability of nuclear energy will drop rapidly away.

            The nuclear power industry is an excellent model of a closed industrial system that is “clean by design” but can never be clean enough or even reliably safe. As a model for other industries that must also conform to closed-system standards, it stands alone, rich with experience and insights and endowed with more than 400 special sites globally that are sacrifice zones,  areas of an increasingly crowded earth available now for no other purpose. Nuclear energy is fascinating and rich in lessons, but it has no potential in resolving the crisis of climate. 

  Adapted from: G.M. Woodwell 2016. AWorld to Live In: An Ecologist’s Vision for a Plundered Planet. MIT, Cambridge               

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